Blade construction: Hira-zukuri Tanto, Iori-mune in low, Kasane is a little on the thick side. Inward curve where upper Fukura area is less swelling.(click HERE for higher resolution image of the entire blade)Forging(Hada): Forging is conspicuous Itame, Mokume and some flowing indication.The surface is covered with fine sparkling Ji-nie glitter to glow mottled Utsuri reflection along Mune back ridge side.Temper(Hamon): Hamon forms shallow wavy in general mixing with tiny irregular quench or small Gunome outline that glows with tight sparkling hard metal granules. Quench boudary line is active with curved mark of Kinsuji threadlike area, Sunagashi short lines of Nie brushing indication here and there. Some YOU flowing quench mark appears in the interior of temper.Temper of tip(Boshi): Temper of tip is strong hard metal granule base, irregular outline with strong Hakikake thick lines of Nie brushing, no return indication.Tang(Nakago): Nakago is in UBU original. Slanting left file marks. One peg hole. Double-bevelled Kurijiri heel shape. Back ridge of Nakago is flat. The signature in front is seven character that reads Bishu Osafune SUKESADA saku 備州長船祐定作 and the reversed side is chiselled with the date of year In the 8th month, Tensho 4 天正四年八月日 (1576).The lineage of sword maker SUKEASADAs 祐定 in Osafune, Bizen province during Muromachi period was one of the most famed and greatest sword makers lined up with 勝光 KATSUMITSU and 清光 KIYOMITSU.The subject cool dagger is designed for the important equipment for an armored Samurai worrier, which is smart and neat, sharp tip, inward curve and a bit long-side palm grip sized tang which is suitable for stabbing into the gap of armor suit.It is quite healthy for the passage of almost 440 years holding almost original volume in Hiraniku and thick in Kasane, deep in Ha-machi edge.The Negoro vermilion-lacquered Toppei style scabbard Aikuchi Koshirae, it's age is on the latter half of Edo period, consists of :1. Negoro style red lacquered scabbard, Oboro-gin silver Kojiri, Kaeri-tsuno and Dou-kane that gives off sober brilliance.2. Solid piece of dimple hard wood hilt, Sakura flower design Menuki of Shakudo, Two wise Monkeys of "see no evil, hear no evil" design kashira of Silver ground, gold, copper and Shakudo inlay.This koshirae holds high sensitivity of creator. The area of scabbard from Dou-kane to Koikuchi entry shows aged mark of cracked, repaired and touch up painted.Old silver foiled copper ground Habaki collar. Comes in Shirasaya plain wood mounting.Condition scale: excellent-very good (using a scale of mint-excellent-very good-good-fair-poor).Old silver foiled copper ground Habaki collar. Preserved in a Shirasaya plain wood mounting.reference data : Three Wise Monkeys